Motor fuel

ABSTRACT

A motor fuel comprising 1-40 volume percent oxylate and 99-60 volume percent light hydrocrackate. The oxylate consists of tertiary butyl alcohol, isopropyl alcohol, and methyl alcohol. Preferred composition for the oxylate is about 20-90 volume percent tertiary butyl alcohol, 540 volume percent isopropyl alcohol, and 5-40 volume percent methyl alcohol. The light hydrocrackate preferably boils between about pentane and 250*F. as opposed to full-boiling-range gasoline, which would boil up to about 430*F. The oxylate improves the octane of the light hydrocrackate gasoline more than expected, and also the oxylate has an unexpectedly high blending octane number in the light hydrocrackate over a wide range of percentage amounts of oxylate in the light hydrocrackate.

United States Patent 11 1 Kozlowski et al.

1 Aug. 26, 1975 1 MOTOR FUEL [73] Assignee: Chevron Research Company,San

Francisco, Calif.

[22] Filed: Nov. 23, 1973 [21] Appl. No.: 418,522

Related US. Application Data [63] Continuation of Ser. No. 163,513, June25, 1971,

abandoned.

[52] US. Cl. 44/56; 260/632 C [51] Int. Cl. C10L 1/08 [58] Field ofSearch 44/56; 208/16, 17

[56] References Cited UNITED STATES PATENTS 15 16,907 11/1924 Backhaus44/56 1,757,837 5/1930 Johns 44/56 1,757,838 5/1930 Johns 44/561,907,309 5/1933 Schaack, Jr.... 44/56 2087582 7/1937 Schneider 44/562,852,356 9/1958 Lichtcnfcls 208/17 2,897,067 7/1959 Sparks ct al. 44/563,172,834 3/1965 Kozlowski 208/17 Rosscup et a1 44/56 Rosenthal 44/56Primary Examiner-Daniel E. Wyman Assistant Examiner-Mrs. Y. H. SmithAttorney, Agent, or FirmG. F. Magdeburger; R. H. Davies; J. J. De Young5 7] ABSTRACT A motor fuel comprising 1-40 volume percent oxylate and99-60 volume percent light hydrocrackate.

The oxylate consists of tertiary butyl alcohol, isopropyl alcohol, andmethyl alcohol. Preferred composition for the oxylate is about 20-90volume percent tertiary butyl alcohol, 5-40 volume percent isopropylalcohol, and 5-40 volume percent methyl alcohol.

The light hydrocrackate preferably boils between about pentane and 250F.as opposed to full-boiling-range gasoline, which would boil up to about430F. The oxylate improves the octane of the light hydrocrackategasoline more than expected, and also the oxylate has an unexpectedlyhigh blending octane number in the light hydrocrackate over a wide rangeof percentage amounts of oxylate in the light hydrocrackate.

7 Claims, No Drawings MOTOR FUEL This is a continuation of applicationSer. No. 163,5l3, filed June 25, 1971, now abandoned.

BACKGROUND OF THE INVENTION The present invention relates to a motorfuel composition comprising hydrocarbons and alcohols. The

motor fuel is particularly intended for use in automocontain leadadditives. However, one of the advantages of the composition of thepresent invention is that it provides a relatively high-octane gasolinewithout the use of lead additives, or with the use of only a relativelysmall amount (e.g., 1.5 cc. alkyl lead additive or less per gallon ofmotor fuel) of lead additive.

The use of alcohols in gasoline-boiling-range hydrocarbons has beensuggested in a number of patents.

For example. U.S. Pat. No. 1,839,362 and U.S. Pat. No. 2,596,198 suggestthe use of methyl alcohol in gasoline.

U.S. Pat. No. 2,662,8 l7 and U.S. Pat. No. 2,726,942 disclose the use ofmethyl alcohol and isopropyl alcohol in gasoline.

US. Pat. No. 2,850,368 discloses the'use of isopropyl alcohol andsecondary butyl alcohol in gasoline, U.S. Pat. No. 2,l97,378 disclosesthe use of isopropyl alcohol and n-butyl alcohol in gasoline.

U.S. Pat. Nos. 2,365,009, 2,404,094 and 2,408,999 all disclose the useof methyl alcohol, isopropyl alcohol, and tertiary butyl alcohol,amongst a wide range of other possible alcohols, for use in gasoline.The latter three patents are directed to major amounts of alcoholcontaining a minor or small amount of hydrocarbon component; forexample, 95 to 90 volume percent alcohol component with only to 10volume percent bydrocarbon component.

In addition to the above patents concerned primarily withalcohol-gasoline compositions, there are a number of patents directed toother additives for gasoline. For example. U.S. Pat. No. 3,083,087 isdirected to use of benzyl esters in gasoline; U.S. Pat. No. 2,874,033 isdirected to the use of isopropyl ether plus isopropyl alcohol ingasoline; and U.S. Pat. No. 1,399,227 is directed to the use of acetonein gasoline.

SUMMARY OF THE INVENTION about 340F.

i We have found that the oxylate'gives an unexpectedly high blendingoctane number in light hydrocrackate, particularly when compared to theblending octane number for the oxylate in full-boiling-range gasolinestocks; that is, gasoline stocks which tend to boil over a wider boilingrange than does light hydrocrackate. Light hydrocrackate, which is usedin the composition according to the present invention, usually boilsbetween about pentane and 250F. Preferably about volume percent of thelight hydrocrackate boils below about 200F. More preferably, at least 90volume percent of the light hydrocrackate boils between pentane and180F. Full-boiling-rangegasoline stocks usually boil between aboutbutane and 430F.; and the 90 volume percent point for full-boiling-rangegasoline stocks is generally considerably above 250F., for example Forabout 5-40 percent oxylate in light hydrocrackate, we have foundtheblending octane number to be about 120, contrasted to a blending octanenumber of about for oxylate in full-boiling-ran ge" gasoline stocks.This unexpected incremental amount for 'the blending octane number ofoxylate in light hydrocrackate compared to oxylate in full-boiling rangegasoline stocks is not expected; thus, oxylate plus light hydrocrackateis a synergistic combination.

In addition to the synergistic result obtained by adding theoxylatecomposition to the gasoline in accordance with the present invention, asecond feature of the present invention is that the oxylate is ofsufficiently high octane number that it can be used to substantiallyincrease the octane number of light hydrocrackate in much the same waythat lead additivesand- /or aromatics are used. Thus, oxylate can beused to reduce the concentration of lead additives and/or aro-Furthermore, an additional (fourth) feature of the composition of thepresent invention is the integration of the light hydrocrackateproduction step with the oxylate production step. The hydrocrackingprocess used to produce the light hydrocrackate produces substantialquantities of isobutane, and it is particularly preferred in producingthe composition of the present invention to use at least a portion ofthe isobutane from the hydrocracking step as at least a portion andpreferably as all-of the isobutane feedstock to the isobutane oxidationstep for the productionof oxylate. According to a preferred embodimentof the present invention, the isobutane which is oxidizedis produced inthe hydrocracking step of an all-hydrocracking refinery, for example, ina refinery process such as described in US. Pat. No. 3,537,977.

A particularly preferred process embodiment for producing a gasolinecomposition in accordance with the present invention (and also havingessentially no aromatics, i.e., less than 2 volume percent aromatics) isas follows. A C,,+ hydrocarbon fraction is fed to a fractionation zoneand split into at least a C -C fraction and a C fraction. The C -Cfraction is isomerized to produce a relatively high-octane (80-90research octane number) product. The C fraction is fed to ahydrocracking zone wherein the C feed is hydrocracked to produce aproduct including light hydrocrackate and isobutane. Effluent from thehydrocracking zone is separated into a propane and lighter fraction, anisobutane fraction, a C -C or approximately lighthydrocrackatc-boiling-range fraction, and a C fraction. The isobutane issubjected to sequential oxidation and hydrogenation to produce oxylatealcohols having a high octane number (BON, about 1 10 or more). The Cfraction or at least a large portion of the C fraction is recycled tothe hydrocracking zone to enable large production of isobutane and lighthydrocrackate from the hydrocracking step. The light hydrocrackate isblended with alcohols and preferably with the isomerization zone productto produce a highoctane, essentially aromatic-free, low-end-pointunleaded gasoline.

The term hydrocracking is used in the present specification to mean acatalytic process carried out at a temperature between about 500 and900F. for the conversion of a hydrocarbon feedstock to more valuablehydrocarbons, particularly including gasoline, by contacting thehydrocarbon feedstock with a hydrocracking catalyst in the presence ofhydrogen gas.

The hydrocracking catalysts used in hydrocracking typically are Group V]or Group VIII metal components with an inorganic refractory carrier suchas alumina and/or silica. Catalytic hydrocracking is a wellknown processand is described, for example, in HY- DROCARBON PROCESSES, September,1968, pages 139-144.

A fifth feature of the present invention, which is very important isthat we have devised a particularly advan tageous process formanufacturing the oxylate for use in gasoline. Instead of starting withfeedstocks such as olefins to obtain alcohols, we start with isobutanefeedstock, which is present in many refineries in excess amounts,particularly refineries wherein hydrocracking is carried out to producegasoline-boiling-range hydrocarbons. In our preferred process theisobutane is oxidized to form tertiary butyl alcohol and acetone plussmall amounts of methanol and esters. This process is described in moredetail in our concurrently filed application entitled GASOLlNEPRODUCTlON" (attorneys docket No. 8-! 812A), the disclosure of whichapplication is incorporated by reference into the present application.The effluent from the oxidation step is hydrogenated to obtain anoxylate mixture comprising tbutyl alcohol, isopropyl alcohol, and methylalcohol.

Thus, with respect to this fifth feature, it can be said in summary thatwe have devised and developed a process to make large amounts ofoxylates in a refinery at relatively low cost for use in a gasolinecomposition.

EXAMPLE Table ll below tabulates data comparing the blending octanenumber (BON) of oxylate in light hydrocrack 5 ate to the blending octanenumber of oxylate in fullboiling-range gasoline.

TABLE ll BON for Oxylate in Full Boiling Range Gasoline BON forOxylatc-Light Oxylate Hydrocrackate' l H) I05 Nil) 90% pt. (ASTM D-8h)2l2; RON 8L5 -907: pt. (ASTM D-Xh) 338; RON 89.5

X Vol. Fract. of base 0,, Octane of base X,, Vol. Fract. of oxylate O,-RON of Blend Although various embodiments of the invention have beendescribed, it is to be understood that they are meant to be illustrativeonly and not limiting. Certain features may be changed without departingfrom the spirit or scope of the present invention. it is apparent thatthe present invention has broad application to motor fuel compositionscontaining oxylate in light hydrocraekate. Accordingly, the invention isnot to be construed as limited to the specific embodiments or examplesdiscussed, but only as defined in the appended claims or substantialequivalents of the claims.

What is claimed is:

l. A motor fuel comprising 1-40 volume percent oxylate and 99-60 volumepercent light hydrocrackate, said hydrocrackate containing essentiallyno aromatics, and said oxylate being a mixture of t-butyl alcohol,isopropyl alcohol and methyl alcohol and containing an amount, basedupon 100 volumes of said oxylate, of tbutyl alcohol in the range 2-90volumes, of isopropyl alcohol in the range 2-50 volumes, and of methylalcohol in the range 2-50 volumes.

2. A motor fuel in accordance with claim 1 wherein the oxylate contains20-90 volume percent t-butyl alcohol, 5-40 volume percent isopropylalcohol, and 5-40 volume percent methyl alcohol.

3. A motor fuel in accordance with claim 1 wherein the oxylate containsabout 40-60 volume percent tbutyl alcohol, about 20-30 volume percentisopropyl alcohol, and about 20-30 percent methyl alcohol,

4. A motor fuel in accordance with claim 1 wherein at least about 90volume percent of the light hydro- 65 crackate boils below 200F.

5. A motor fuel in accordance with claim 1 wherein at least 90 volumepercent of the light hydrocrackate boils between about pentane and [80F.

6 7. A process in accordance with claim 5 wherein the motor fuel isprepared at least in part by blending light hydrocrackate from ahydrocracking process with the oxylatc, and wherein the oxylate isprepared at least in part by the oxidation of isobutane from saidhydrocracking process.

1. A MOTOR FUEL COMPRISING 1-40 VOLUME PERCENT OXYLATE AND 99-60 VOLUMEPERCENT LIGHT HYDROCRACKATE, SAID HYDROCRACKATE CONTAINING ESSENTIALLYNO AROMATICS, AND SAID OXYLATE BEING A MIXTURE OF T-BUTYL ALCOHOL,ISOPROPYL ALCOHOL AND METHYL ALCOHOL AND CONTAINING AN AMOUNT, BASFEDUPON 100 VOLUMES OF SAID OXYLATE, OF T-BUTYL ALCOHOL IN THE RANGE 2-90VOLUMES, OF ISOPROPYL ALCOHOL IN THE RANGE 2-50 VOLUMES, AND OF METHYLALCOHOL IN THE ANGE 2-50 VOLUMES.
 2. A motor fuel in accordance withclaim 1 wherein the oxylate contains 20-90 volume percent t-butylalcohol, 5-40 volume percent isopropyl alcohol, and 5-40 volume percentmethyl alcohol.
 3. A motor fuel in accordance with claim 1 wherein theoxylate contains about 40-60 volume percent t-butyl alcohol, about 20-30volume percent isopropyl alcohol, and about 20-30 percent methylalcohol.
 4. A motor fuel in accordance with claim 1 wherein at leastabout 90 volume percent of the light hydrocrackate boils below 200*F. 5.A motor fuel in accordance with claim 1 wherein at least 90 volumepercent of the light hydrocrackate boils between about pentane and180*F.
 6. A motor fuel in accordance with claim 1 wherein the oxylate isprepared at least in part by a process which comprises oxidizingisobutane to obtain t-butyl alcohol, acetone, and methyl alcohol, andthen hydrogenating the effluent from the oxidation step to obtain amixture comprising t-butyl alcohol, isopropyl alcohol, and methylalcohol.
 7. A process in accordance with claim 5 wherein the motor fuelis prepared at least in part by blending light hydrocrackate from ahydrocracking process with the oxylate, and wherein the oxylate isprepared at least in part by the oxidation of isobutane from saidhydrocracking process.